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High-performance large-format detector arrays responsive to the 1-5μm wavelength range of the infrared spectrum
fabricated using large area HgCdTe layers grown on 6-inch diameter (211) silicon substrates are available for advanced
imaging applications. This paper reviews performance and capabilities of Raytheon Vision Systems (RVS) HgCdTe/Si
Focal Plane Arrays (FPA) and shows 2k x 2k format MWIR HgCdTe/Si FPA performance with NEdT operabilities
better than 99.9%. SWIR and MWIR detector performance for HgCdTe/Si is comparable to established performance of
HgCdTe/CdZnTe wafers. HgCdTe devices fabricated on both types of substrates have demonstrated very low dark
current, high quantum efficiency and full spectral band fill factor characteristic of HgCdTe. HgCdTe has the advantage
of being able to precisely tune the detector cutoff via adjustment of the Cd composition in the MBE growth. The
HgCdTe/Si detectors described in this paper are p-on-n mesa delineated architecture and fabricated using the same
mature etch, passivation, and metallization processes as our HgCdTe/CdZnTe line. Uniform device quality HgCdTe
epitaxial layers and application of detector fabrication processes across the full area of 6-inch wafers routinely produces
high performing detector pixels from edge to edge of the photolithographic limits across the wafer, offering 5 times the
printable area as costly 6×6cm CdZnTe substrates. This 6-inch HgCdTe detector wafer technology can provide
applications demanding very wide FOV high resolution coverage the capability to produce a very large single piece
infrared detector array, up to a continuous image plane 10×10 cm in size. Alternatively, significant detector cost
reduction through allowing more die of a given size to be printed on each wafer is possible, with further cost reduction
achieved through transition towards automated detector fabrication and photolithographic processes for both increased
yields and reduced touch labor costs. RVS continues to improve its FPA manufacturing line towards achieving low cost
infrared FPAs with the format, size, affordability, and performance required for current and future infrared applications.
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